Question: Simplify the following expression: $x = \dfrac{k}{3} + \dfrac{k}{4}$
Solution: In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $3$ and $4$ $\lcm(3, 4) = 12$ $ x = \dfrac{4}{4} \cdot \dfrac{k}{3} + \dfrac{3}{3} \cdot \dfrac{k}{4} $ $x = \dfrac{4k}{12} + \dfrac{3k}{12}$ $x = \dfrac{4k +3k}{12}$ $x = \dfrac{7k}{12}$